For certain types of syntax error in a regular expression pattern,
the error message could either contain the contents of a random,
possibly large,
chunk of memory,
or could crash perl.
This has now been fixed.
[perl #131598]

Several built-in functions previously had bugs that could cause them to write to the internal stack without allocating room for the item being written.
In rare situations,
this could have led to a crash.
These bugs have now been fixed,
and if any similar bugs are introduced in future,
they will be detected automatically in debugging builds.
[perl #131732]

Using a symbolic ref with postderef syntax as the key in a hash lookup was yielding an assertion failure on debugging builds.
[perl #131627]

List assignment (aassign) could in some rare cases allocate an entry on the mortal stack and leave the entry uninitialized.
[perl #131570]

Attempting to apply an attribute to an our variable where a function of that name already exists could result in a NULL pointer being supplied where an SV was expected,
crashing perl.
[perl #131597]

The code that vivifies a typeglob out of a code ref made some false assumptions that could lead to a crash in cases such as $::{"A"} = sub {}; \&{"A"}.
This has now been fixed.
[perl #131085]

my_atof2 no longer reads beyond the terminating NUL,
which previously occurred if the decimal point is immediately before the NUL.
[perl #131526]

The list above is almost certainly incomplete as it is automatically generated from version control history.
In particular,
it does not include the names of the (very much appreciated) contributors who reported issues to the Perl bug tracker.

Many of the changes included in this version originated in the CPAN modules included in Perl's core.
We're grateful to the entire CPAN community for helping Perl to flourish.

For a more complete list of all of Perl's historical contributors,
please see the AUTHORS file in the Perl source distribution.

If you believe you have an unreported bug,
please run the perlbug program included with your release.
Be sure to trim your bug down to a tiny but sufficient test case.
Your bug report,
along with the output of perl -V,
will be sent off to perlbug@perl.org to be analysed by the Perl porting team.